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61.
本文应用VPN组网技术,全省各地的下属单位通过互联网建立与省局局域网虚拟专网隧道,通过配置防火墙的IP访问控制,获取访问省局局域网中的学位论文服务器的指定IP地址范围和必要权限,查阅相关学位论文,有助于开展各项科学研究工作。  相似文献   
62.
“数字城市”的空间数据库设计方法研究   总被引:1,自引:0,他引:1  
万剑华  刘娜  马张宝  孟慧 《测绘科学》2006,31(6):107-108
本文简单介绍了“数字城市”的背景和理论基础,并对常用的Access、SQL Server、Oracle数据库进行对比分析与研究,总结了各自的优缺点;分别从数据库的结构设计、数据库的功能设计、数据库的界面设计、基础数据库的建立等方面提出了“数字城市”的数据库的设计与建设方案,并成功运用在“数字东营”的数据库建设中。  相似文献   
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64.
The Marine and Coastal Access Bill, when it becomes law, may well be considered a welcome addition to the legislation protecting the marine coastal environment. It is argued, however, in this paper that the Bill could have addressed a number of issues including the matter of shipowners’ privileges, locus standi, the designation and setting up of an environmental fund, and the difficulties associated with places of refuge for vessels in distress.  相似文献   
65.
分析了动态网页访问控制的现状和需求,提出了一种动态网页细粒度策略自适应访问控制模型(FPAAC),并在开发的模拟系统中进行了验证。  相似文献   
66.
南岭地区锡多金属矿床空间数据库建设是国家地质调查主管部门和南岭地区新一轮地质勘查、矿产开发的需要.数据库在Microsoft Access 2000和Mapgis软件中编辑制作,包括ACCESS(.mdb)和MAPGIS点文件(*.WT)两种格式的文件,由矿床基本情况与矿区地质情况两张基本表格和相应的表单、查询组成,矿...  相似文献   
67.
Roman Grynberg   《Marine Policy》2003,27(6):499-511
The paper considers the WTO negotiations on fisheries subsidies and the implications that envisaged disciplines will have on coastal developing countries. This is considered in relation to fisheries access agreements in the Central and Western Pacific where several least developed but resource rich island states such as Kiribati and Tuvalu are highly exposed to the risks associated with new WTO fisheries subsidies disciplines that do not consider their particular vulnerabilities. The paper considers some of the issues that coastal developing countries should incorporate into their emerging negotiating positions at the WTO. State-to-Sate fisheries access agreements which are often highly subsidised but where fishing vessel owners pay the equivalent of lump sum tax are paradoxically, the least distortionary and damaging to the environment. Strategies for managing the possible new disciplines are considered.  相似文献   
68.
Transportation infrastructure has always played an important role in the economic fate of regions. In particular, airline networks have dramatically decreased the geographic and temporal constraints of moving people, goods and information; all of which are increasingly crucial inputs for the information economy. As a result, regions have become more concerned with both the quantity and quality of airline connections. The purpose of this paper is to examine the emerging global hierarchy of airline network connectivity. Using a proprietary database of nearly 900 airline carrier schedules from 2006, we examine regional connectivity between 4,650 worldwide origins and destinations. Through the use of network analysis and graph theoretical techniques, results indicate an increasingly complex web of nodal hierarchies in North America, Europe and Asia.
Tony H. GrubesicEmail:
  相似文献   
69.
随着空间定位技术的普及,不同空间直角坐标系间的转换过程中经常遇到问题不易被解决。本文首先介绍了不同空间直角坐标系间转换时广泛使用的布尔沙转换模型并阐述了七参数求解的过程,然后结合ACCESS中的表、窗体和宏,利用VBA实现了基于布尔沙转换模型的七参数计算程序,并结合实例对所编写的程序加以验证,保证其结果的可靠性。  相似文献   
70.
The tuna industry in the Western and Central Pacific Ocean (WCPO) is one of the most valuable fisheries in the world. Taiwan has a long fishing history and is one of the major distant water fishing nations in the surrounding area. This study aimed to review the historical cooperation structure between Taiwanese purse seiners and Pacific Island Countries (PICs). Data were collected by literature analysis and semi-standardized in-depth interviews with experts. The results showed that since 1982, the Taiwanese purse seiners have developed and signed bilateral access agreements with seven PICs under a variety of formats. The fisheries access and licensing arrangements have been transformed to a Vessel Day Scheme (VDS); as a result, the access fees have increased rapidly since 2010. Taiwanese industries have invested in facilities and share ownership with some PICs. Moreover, the Taiwanese purse seiner industries have proclaimed their willingness to follow the Western and Central Pacific Fisheries Commission conservation measures and stated that they will cooperate with PICs. They hold conservative views, however, regarding the further transfer of ownership to PICs. For the conservation of tuna resources in the WCPO, distant water fishing nations and PICs should cooperate to limit fishing capacity and ensure that the access fee benefits PICs.  相似文献   
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